Thallium-201 is a radioactive isotope that undergoes first-order decay. when the concentration of 201tl is 0.0042 m, its half-life is 73.0 hours. what is the half-life of 201tl when its concentration is 0.0136 m? (a) 51.0 hours (b) 73.0 hours (c) 123 hours (d) 236 hours

Sugar is made up of clear, colorless crystals that dissolve easily in water, but the crystals and their solution do not conduct electricity. which statement describes sugar? it is made up of atoms that are held together by metallic bonds. it is made up of atoms that are held together by covalent bonds, it is made up of atoms that are held together by weak ionic bonds. it is made up of atoms that are held together by strong ionic bonds.